Metallic-filament lamp.



0. KRAUSE.

f METALLIC FILAMENT LAMP.

' APPLIUATION FILED 00T. 1B, 1909. 1,041,81 7,' Patented Oct. 22, 1912.

4 SHEETS-SHEET 2.

n @mug O. KRAUSE.

METALLIC FILAMENT LAMP.

, `9. 1,041,81 7. Patented oct. 22, 1912.

4 SHEETS-SHEET 3.

17m/enf or ora m94 asf o. KRAUSB.

METALLIC PILAMBNT LAMP.

Arrmonron FILED ooT.1e, 1909.

' 4 SHEETS-SHEET 4.

Unvenor Wz'zlnesses v l arm imm/.sfr

` lamp.

` AUNITED STATES PATENT FFICE.

oTTo KRAUASE, or BERLIN, GERMANY, AssIGNoR, BY MEsNE ASSIGNMENTS, To GENERAL ELECTRIC COMPANY, A CORPRATION OF NEW YORK.

METALLIC-FILAMNT LAMP.

Specification of Letters Patent.

Patented oct. 22,1912.

Application' led October 16, 1909. Serial No. 522,910.

.To all 'who-m it may concern:

Beit known that I, O'rro KRAUSE, a sub.

lamps wherein the metallic filaments areV mounted upon filament carriers independent of the lamp body, the filament carrier being elastically supported upon or in connection with the lamp body, or some part thereof.

The methods hitherto known for arranging elastic filament carriers in metallic filament glow lamps are imperfect for several reasons.

If the center glass rod is elastically connected with the foot of the lamp by means of a spring and with the tip of the lamp by a second spring it involves considerable difculties in the manufacture, viz., in the handling ofthe filament carriers and also during the sealing of same into the glass bulbs. lf the spring is dispensed with at the tip of the lamp it frequently happens `that vibrations of the whole of the filament carriers of a naturev similar to those of a tuning fork may cause amplitudes of movenient which allow the filament to touch the walls in ordinary sized lamp bulbs and thus easily lead to the destruction of the whole rihe use of extensions of the center rod in the form of elastic wires which reach the tip of the bulb has also failed to givei satisfactory `results, as the manufacture becomes more ditlicult and cracks which may occur in the glass influence the safety of the air tight sealing ofli' of the bulbs. Furthermore in lamps the carrier of which is only connected with the foot of the lamp by a spring, the length of such spring is very small in the direction of the axis relative to thewixial length of the filament carrier.`

i ranged rods e.

part of the filament carrier which is near the spring.' In consequence the spring is either not sufficiently elastic in regard to the parts of the carrier near the spring or too elastic regarding the more remote parts. The present invention removes this diiculty.

It consists in attaching to the foot of the lamp a center rod whichis arranged axially and is surrounded concentrically by a cylindrical or prisinatical part which forms the filament carrier. The connection between the center rod and the filament carrier proper is formed by springs, or the stein it self consists of an elastic material.

`The manner of carrying out my invention may vary in very many respects as will presently be described. Common to all is the thought that the upper part of the lament carrier and the lower part which is near the foot of the lamp perform essentially amplitudes of the same len th, so that the danger of an injury to the aments by their touching the walls of the lamp bulbs is avoided. I

In the drawings Figure 1 illustrates the invention as applied in t-he form of a cylindrical frame elastically supported at each end; Fig. 2 in the form of a cylindrical tube, Fig. 3 illustrates a inodication of Fig. 2 showing a special form of spring; Figs. 4, 5, 6, 7, 8, and 9 illustratevarious modifications of the elastic support; Fig. 10 illustrates a inodication in which the spring connections lie outside of the cylindrical frame; Fig. 1l illustrates a frame provided with a central constriction; in Figs. 12 and 13, the frame is shown as constricted or reduced in size at its extreme end and Fig. 14 illustrates a lamp in which the spring support is located at the center of gravity of the filament carrying frameand having special springs serving as current conductors outside of the lament carrier.

As a mode of carrying out this invention Fig. 1 shows a lamp foot a onrwhich the center rod b is fixed. This rod, say a glass rod is surrounded by a cylindrical .frame consisting of two circular end pieces c and a. which are connected by several axially ar- This.frame is for inst-ance connected with the center rod by two groups y each havingd three springs j and g. The

yfilament ho ers k and 21 and the leading-in wires la are fixed to the circular end pieces c and d.

As shown in Fig-2 the rigid center rod is surrounded by'a cylindrical tube e' of glass or any other suitable material while the elastic connection is made in a manner similar to that shown in Fig. 1.

It is advantageous to make the stem I) somewhat longer than heretofore and to arrange the springs f and c/ for supporting theA filament carrier in a slightly inclined position. The stem may also be hollow whlch will facilitate the fixing of the springs.

The mode of carrying out the invention shown in Fig. 3 differs from the above examples in that the elastic connection between the center rod and the filament carrier surroundlng 1t conoent-rlcally 1s made' by ymeans of pleces of watch spring and which also insure' the vibration of the filament carrier causing a parallel displacement of the whole frame.

Fig. 4 shows two other examples of suitable simple springs f and g. Each of these Asprings actually consists of three or more parts and not of two parts only as appears from the illustration. Two 'divided springs can be used as shown'in f or two springs also consisting of several parts may be applied as illustrated in g. These springs are fixed to the axial stem b and' theinfree ends are adapted to slide along the-inner walls of the tubular filament carrier e until they find their seats in annular pockets of the same.

Fig. a illustrates another example of the elastic arrangement. Springs f and g extending outward and springs f and g extending inward `are fixed respectively on rings Z,'Z, each of a diameter smaller than that of the tube e but larger than that of the rod b. The former set of springs touches the filament carrier, the latter touch the stem. Only two springs are shown in the illustration, in practice however .at least three springs are used. The springs are advantageously/formed in such a way that at the point where they touch the glass rod they are in Contact not at individual points but for a considerable extent of surface. It is also, advantageous thatthe stem b be somewhat constricted at the points where the springs Iare applied, and that the `filament carrier e -be' somewhat enlarged at such points.

The two rings'l, Z, in Fig. 5 are shown as independent of each other but they may, if desired, be connected directly one' with the other so as to produce a single spring piece f, f', l, g, g instead of two separate and disconnected spring piecesf, f', Z and g, g', l.

It is unnecessary to describe further analogous ways of carrying out the invention as vaxial stem near the foot of the lamp.

the invent-ive idea is made suiiciently clear by the examples abovel described. The

springs may have any desired form and j touch at any suitable pointsthus answering the purpose of effecting an approximately parallel movement of the filament carrier in case it should be exposed to shock.

Sometimes modifications of the said; inventive idea prove advantageous. whereby 'the connection between the tubular filament carrier and the stem placed axially within it is formed by a joint which may be fixed at any point of the tubular part of the filament carrier but preferably at its center.

The inner part 0 of the movable or joint like` connection/such as a ball and socket joint can advantageously be formed by three' metal strip. In the arrangement as shown in Fig. 9 the arms of the inner part of the joint c which have vthe form of a. segment of a circle are of such dimensions that they Will only allow the filament carrier to slide over the stem for the purpose of manufaclture, but which do not appreciably yield in consequence of shocks inflicted on the lamps.

The axle stem b may be either rigid (see Fig. 6) or inherently elastic, as shown for instanceinFigs. 7 and 8. In these last two figures the axle stem is shown as composed of Iflexible arms joined near the lamp foot and terminating at `,their free ends infthe ball like spring connections. In Fig.' S, the terminal Vspring fingers c have a short straight extension c lying snugly against.

the inner face vof' the tubular frame and thus serve to limit oscillations thereof.

All these modiicationshave in common an elastic connection between the lower part of the filamentcarrier with the lamp foot c lconsisting of special springs e which asshown 1n the illustrations serve at the same time as current conducting-wires. The ef.- fect of this arrangement remains the vsame when springs of other suitable forms particularly in groups of two or more are used for the connection of the filament carrier with the lamp foot, or with that part of tlhe n the latter case it is sufficient if the leadingin-wires are iexible.

With 4regard to the point where the-joint l connection of the filament carrier with the axial stem is to be placed comparative experiments have proved the superiority of such arrangements where this joint is placed at the center of gravity of the filament carrier or in immediate proximity thereto.

Instead of enlarging the tubular filament carrier 1t may also be provided with vconstrictions. In such case the wires forming 'the inner part of the joint are bent concavely in order to fit the constrictions.

For esthetic reasons the filament carrier can be made of opal 'glass instead of clear 'to the filament carrier concentrically surrounding it, or to the filaments fastened thereon will be obviated. The surface of the axial stem acts as a guide to the filament 'carrier surrounding -it in such a manner that a sllght mcllnation may take place be-` tween the stem and the filament carrier.

Fig. 10 illustrates such a form of carrying out the invention, the axial stem being place'd through the central bore of the disk c which in itself is suitably connected with the tubular part of the filament carrier d.

Figs. 11, 12, and 13 show the tubular part of the filamentcarrier with a constriction.

, This constricted part is arranged near the middle of the tube (Fig. 11). It can however also be placed near the end of the tube d (Figs. 12 and 13).A v

Such oscillations of the elastic stem as are transmitted to the filament carrier are takenV up and deadened by the action lof special springs e, which connect the filament carrier with the lamp foot a or with a part of the axial stem near the foot of the lamp. In the modification shown in'Fig. 10 this effect is produced by the use of spiral springs e which at the same time serve as current conductors to the filament carrier and which can bemade of any suitable material such as copper, nickel, etc.

Fig. 11 illustrates an arrangement in which the filament carrier d is elastically connected with a glass disk f fixed to the lower part of' the stem by means of a group of three spiral springs e. i

The springs as shown in Fig. 12 are arranged similarly to those in Fig. 10 while in Fig. 13 the connection between the filament carrier and the stem consists of a single spiral spring.

Those modifications yhave proved most effective in carrying out this invention in which the point at which the lament carrier is guided by means of the axial stem (starting from the lamp foot) is at or as near as practicable to the center of gravity of the filament carrier.

A simplified manner of obtaining the de- -sired object consists in a modification whereby in the interior of' the tubular filament .carrier a single spiral spring is arranged as near as possibleto the center of gravity for l the purpose of establishing an elastic conlnection with the axial stein, while special springs which may advantageously serve as current conductors are placed outside the filament carrier take up the remaining oscillations ofthe filament carrier.

Fig. 14 is an illustration: a is the foot of the lamp, b the axial stem which is fixed to the lamp foot, c is a spiral spring for the connection of the stem and the tubular filament carrier d and e are the special springs which connect the lower part of the filament carrier with the foot of' the lamp and serve at the same time as the current conducting wires.

I claim: j

1'. The combination of an axially open filament holder, a filament wholly supported on said holder, a stem projecting into said open holder, said stein being normally out of contactwith said holder and an elastic support to maintain said holder in the lamp.

2. The combinationv of an axially open filament holder, a filament wholly supported on said holder, a stem projecting into said open. filament holder having a cylindrical tubular form, said stem being normally out of contact with said holder and an elastic support to maintain said holder in the lamp.

3. The combination of an axially open filament holder, a filament wholly supported on said holder, a stem projecting into said open holder, said stem being normally out of contact with said holder and an elastic support to maintain 'said holder in the lamp, said elastic support comprising a plurality of springs operating on different portions of said holder.

4. The combination l of an axially open filament holder, a filament wholly supported on said holder, a stem projecting into said open holder, said stem being normally out of contact with said holder and an elastic support to maintain said holder in the lamp, said elastic support comprising a plurality of springs operating on different portions of said holder, each spring having several gripping surfaces.

5. The combination of an axially open filament holder, a filament wholly supported on said holder, a stem projecting into said open holder, said stem being normally out of contact with said holder and an elastic support to maintain said holder in the lamp, said elastic support being interposed Y between the stem and the filament holder.

6. The combination ofl an axially open filament holder, a filament wholly support edv on said holder, a stem projecting into said open holder, said stem being normally out of contact with said holder and an elastic support to maintain said holder in the lamp, said elastic support being interposed between the stem and the filament holder and consisting of springs, an Lelastic portion :of which presses inwardly against the stem and an elastic portion of which presses .out-

wardly against the filament-holder.

7. The combination of an axially open filament holder, a filament wholly supported on said holder, a stem projecting into said open holder, said stem being normally out of contact with said holder and an elastic sup port to maintain said holder in the lamp,

10,said elastic support comprising an elastic connection between the filament holder and the stem and an elastic connection between ythe filament holder and the lamp body. 8.. The combination of an axially open filament holder, a filament wholly supported on said holder, an elastic stem projecting into said open holder and an elastic support carried by said stem and connecting with said holder and an elastic-support consisting of springs connecting the holder with the lamp body near the lamp foot.

9. The combination of an axially open filament holder, a filament wholly supported on said holder, an .elastic stem projecting into said open holder and adapted to contact i v with a rigid portion of said holder and an elastic support connecting the holder with the lamp body near the lamp foot.

10. The combination of an axially open filament holder, a filament wholly supported on said holder, a 'stem projecting into said open holder and anelastic support to maintain said holder in the lamp, said elastic support being arrangediat approximately the center of gravity of the filament holder.

11. The combination of an axially open filament holder, a filament wholly-supported on said holder and an elastic support to maintain said holder inthe lamp, said elastic support comprising as a unit an axial Astem projecting into the open holder, said Astem terminatlng in al number of flexed strips, said strips making contact with the filament holder.

12.*The combination of, filament holder, \on said holder, a stem projecting into said open holder and leading-in wires connected with the filament and formed into springs 1for elastically maintaining the holder in the l?? The combination of filament holder,

an axially open a lament wholly supported an axially openy a filament wholly supported on said holder, a stem projecting into said Lopen holder, meanslocated approximately at the' center of gravity of the holder for cooperation with the stem and an elastic support to maintain said holder-in the lamp.

14.-. The combination of an axially open holder, a filament wholly supported on said holder, and means for resiliently supporting said holder in the lamp comprising a stem projecting into said open holder and normally out of contact therewith.

15. The combination of an axially open holder, 4a filament supported on said holder, and means for resiliently supporting the holder in the lam comprising parts adapted to operate on di erent parts ofthe holder, said means including a stem projecting into the holder and normally out of contact therewith. l

16. The combinationof an axially open filament holder, al filament wholly supported on said holder, and means forlresiliently maintaining said holder in position in the lamp comprising a stem projecting into the holiler and normally out of contact therewit v 17. The combination of a hollow filament holder, a filament wholly supported on the exterior of said holder, and yielding means for maintaining said holder in the lamp which acts thereon through engagement with its interior and includes a 'supporting means projecting thereinto but normally out of contact therewith. 18. The combination with an incandescent lamp foot, a hollow holder, a filament wholly supported o'n the exterior of said holder, and means for 'resiliently supporting said holder from 'the lamp' foot compr1s`1ng a part projecting into the holder, said means including elastic parts by which .vibrationof said holder with reference to the lamp foot is allowed, parts of said holder equally distant from a point within its interior vibrating through eq'ual amplitudes. In witness whereof have hereunto signed my name this twenty-second. day ofl September 1909 in the witnesses.

OTTO 'KRAUSE Witnesses:

HENRY HAsrER, WOLDEMAR HAUPT.

presence of two subscribing 

